'No, not for a moment' The Doctor smiled. 'But we live in hope.'

'You can read them?'

The Doctor shone his torch at the nearest set. 'Not yet.

I've a gift for languages, though. Give me a few minutes and I might be able to cobble something together.'

'Doctor! Look!' Nyssa was pointing back towards the mouth of the tunnel. The spiders had already started to rebuild their cobweb: across the entrance, running busily to and fro.

'Closing the door behind us, as it were,' remarked the Doctor. 'Charming.'

'Here we are,' said Stoker. 'Pay dirt.'

She was slouched at Lawrence's computer terminal.

Lawrence had just used his OC emergency override to break through the personal security codes on Silas Cadwell's private files.

'I'm not sure we should be doing this,' Lawrence said. He felt distinctly uncomfortable about the whole affair now, particularly the way in which Stoker was sprawling over his desk. She was still clearly under the influence of the Kalazak brandy and Lawrence felt that he, for one, should know better than to attempt something as morally dubious as this. But there was something about Stoker, even when she was drunk, that he found difficult to resist.

She was laughing at him now. 'Lighten up. That was always your problem, you know that? You always had to stick to the rule book.'

'Do the right thing, you mean.'

'I mean you had no imagination. If it wasn't in a textbook you didn't want to know.'

'But at least I did know know what was in the textbook. Unlike some.' what was in the textbook. Unlike some.'

'And another thing,' she said, leaning closer. 'You were always so b.l.o.o.d.y b.l.o.o.d.y good-looking.' good-looking.'

Lawrence took his eyes off the screen and met her stare.

'You're drunk.'

'd.a.m.n right. Kiss me.'

'Don't be ridiculous.'

'What's up? Isn't kissing in the rule book?'

'Let's just concentrate on the matter at hand, shall we?'

'OK. You're right, I'm drunk,' Her eyes twinkled amber at him. 'We'll play it by the rules.'

'I wish,' Lawrence grumbled ruefully.

Stoker's fingers tapped at the keys for a few seconds.

The files that had shown up under Cadwell's name and codes were all disappointingly mundane, except for one.

'What's this then, Silas?' Stoker wondered aloud. 'It's pretty big, whatever it is?

Lawrence frowned. 'It's some sort of data cache.'

And it's firewalled,' Stoker realised. She slapped the keyboard in frustration. 'Old-fashioned but effective.'

'But why would Cadwell need to security-lock a file that was already security locked?'

'Isn't it obvious? Because the first security lock can be overridden by you.'

Lawrence bit his lip. 'This is serious. Can you get through the firewall?'

'Hey, I didn't waste all all my time at the Academy.' Stoker worked on the keyboard a little longer, but the files refused to open up whatever she tried. 'Enter your command override again,' she instructed Lawrence. my time at the Academy.' Stoker worked on the keyboard a little longer, but the files refused to open up whatever she tried. 'Enter your command override again,' she instructed Lawrence.

'Tell it whatever you have to: the planet's about to blow up, sun's going nova, you've lost your boot polish, anything anything to make the puter think it's a real emergency.' to make the puter think it's a real emergency.'

'I've already done that.'

'Do it again,' she told him, 'with meaning this time.'

He entered the command code. 'This is hopeless,' he said.

'Wait,' Stoker said. 'Look at this: you've not accessed the file but you've cracked the file name.'

Lawrence leaned forward and stared at the screen. 'What the h.e.l.l's that supposed to mean?' he muttered.

Stoker sat back in her seat, puzzled. Something cold crawled around her neck as she read the file name out aloud: ' The Dark.' The Dark.'

The Doctor had made a rapid and intense study of the strange, unworldly hieroglyphics that covered the tunnel walls. His examination had led them further into the pa.s.sageway. As they went deeper, the runes seemed to change, becoming less structured and rigid, and more free-flowing and expressive.

'I'm afraid these runes tell an unpleasant story' said the Doctor.

'You surprise me.'

'I can't make out all the details, but it seems to concern the legend of an evil being that was once reduced to ashes and buried forever.'

The Doctor paused. 'At least I think that's what it says.'

'Buried here?' Nyssa queried.

'Probably.'

'Then this is a crypt, or a tomb, after all.'

'Yes. It's ironic, isn't it? Stoker's team claimed to be a team of archaeologists when we first arrived, looking for the remains of an ancient alien civilisation. All completely false, of course. Or so they thought!'

'Does it say what the being in the legend was? The one that was reduced to ashes and buried forever?'

The Doctor scratched his head. 'Well, no, not in so many words. It all seems to get a little vague. As far as I can make out, a party of men came to the planet Akoshemon centuries ago - that's a guess and battled with the evil that lived in the hearts and minds of...' his fingers traced the lines of an ugly pictogram, 'the monsters, I think it means, which inhabited it.

The battle lasted for... well, for a very long time. Generations were sacrificed. Ultimately they triumphed, although at great cost.'

'But what was it they fought, exactly?'

'I don't know. It just keeps going on about darkness, or the dark the dark at any rate.' at any rate.'

Nyssa shuddered. 'Then it is is here.' here.'

'Yes. But dead, remember. Reduced to ashes and buried Reduced to ashes and buried forever.' forever.'

'You once told me one shouldn't believe everything one reads.'

'Ah, yes. Quite true.' The Doctor rocked on his heels for a moment.

'There's only one thing for it,' he said. 'We'll have to check. Come on!'

'Must we?'

'This is what we came here to find, Nyssa,' the Doctor reminded her sternly.

'I know, but... I can't go on. The atmosphere down here is so thin and oppressive, Doctor. I have this feeling of terrible dread that... that something awful is going to happen.'

The Doctor peered into her eyes. 'I understand what you mean, Nyssa. I can feel it too, and it's been growing stronger every step of the way. It wants us wants us to fear it. It's tampering with our perceptions, remember. But if it's trying to put us off, then there must be a good reason: perhaps it's weak now, vulnerable. This could be our best chance to find out exactly what it is and stop it.' to fear it. It's tampering with our perceptions, remember. But if it's trying to put us off, then there must be a good reason: perhaps it's weak now, vulnerable. This could be our best chance to find out exactly what it is and stop it.'

He took her hand in his and led her gently down the tunnel. The shadows seemed to be congealing around them, and Nyssa felt her heart straining in her chest. She knew the blood running in her veins was as thick and black as these shadows; she could feel the presence of her dream-voice close by, whispering to her just beyond the edge of hearing.

Presently they emerged into a large, circular chamber.

The light in here was green and murky, emanating from a domed ceiling where hundreds of glow-worms snaked through the translucent rock like veins.

The floor of the chamber sloped sharply down to some kind of pit or well in the exact centre. The Doctor and Nyssa came to an unsteady halt at its edge. The Doctor hesitated for a second, staring into the dark hole, but could see nothing. It appeared to be completely black.

'What is it?' Nyssa asked with a shiver. There seemed to be a coldness surrounding the pit that she could feel deep inside her, as though her bones were slowly turning to ice.

'I can't tell, it's too dark' The Doctor spoke softly but his voice echoed around the chamber. He aimed his torch directly into the black pit. 'It's full of some kind of tar or slime... I can't see it properly. It's absorbing the torchlight!'

Nyssa was shaking. The Doctor saw her and looked uneasy. 'What's the matter? Can you feel it? Is this it? The enemy?' He pointed at the black pit.

She nodded dumbly, hugging herself but unable to stop quivering.

I am here She gasped. The voice was so close, right inside her head, behind her eyes.

I am so close to you Waiting Trapped 'Nyssa!' the Doctor said sharply. 'Snap out of it! Resist it, Nyssa!'

She closed her eyes and shuddered violently, feeling her legs weakening beneath her. Then she felt the Doctor's arms as he caught her awkwardly and they knelt together by the edge of the pit.

'It's here,' she said raggedly. 'Waiting...'

'What is it waiting for?'

'Its servant...'

The Doctor looked pained. 'You, Nyssa? Is it you?'

Nyssa opened her mouth to speak but nothing came. Her eyes were rolling up into her head. The Doctor grasped her face roughly with the fingers of one hand and made her look at him. 'Let me communicate with it, Nyssa. Let me talk to it!'

'I can't... it's not ready...'

The Doctor let out an exasperated hiss.

For a long, cold moment there was utter silence.

Then they both heard the noise at the same time: the soft rustle of something approaching from the rune-lined pa.s.sage behind them.

Nyssa turned to look at the Doctor, horrified. 'The Bloodhunter!'

The Doctor quickly pulled Nyssa back from the edge of the pit and they crouched down by the wall, away from the tunnel entrance.

The creature entered the chamber and paused for a moment on the threshold, as if waiting or listening.

Then the Doctor and Nyssa watched it step forward, right to the very edge of the pit at the centre of the room. The Bloodhunter raised its hands, almost in an att.i.tude of worship. The creature's liver-coloured head shone in the torchlight and then it knelt down as if in prayer.

Nyssa tore her gaze from the creature and looked at the Doctor, who was staring in wide-eyed fascination.

The creature was leaning forward, peering into the oily black depths of the pit. A shudder pa.s.sed through its body and it coughed violently.

Then, with a sudden convulsion, it threw its head forward and vomited a stream of dark liquid into the pit.

'What's happening?' Nyssa gasped in revulsion.

'It's regurgitating the blood,' the Doctor told her.